The present disclosure relates to an image forming apparatus for forming an image on a sheet, and more particularly, to an image forming apparatus provided with a static eliminator for irradiating a photosensitive drum with static eliminating light.
Conventionally, in an image forming apparatus for forming an image on a sheet, a toner image is formed on a circumferential surface of a photosensitive drum, and the toner image is transferred onto a sheet in a transfer portion. The image forming apparatus is further provided with a fixing portion. A sheet carrying a transferred toner image is subjected to a fixing process in a fixing portion, and then discharged to the outside of the apparatus.
A cleaning member removes toner that remains on the circumferential surface of the photosensitive drum after the transfer operation. Additionally, a static eliminator is disposed to face the photosensitive drum and removes the electric charges remaining on the circumferential surface of the photosensitive drum after the cleaning operation. The static eliminator irradiates the circumferential surface of the photosensitive drum with static eliminating light to remove the remaining electric charges.
A photosensitive drum is required to be dismounted from the image forming apparatus main body for replacement. In view of the above, the photosensitive drum is integrally supported on a drum unit, and is dismountably mounted to the image forming apparatus main body. Generally, the life of a static eliminator is long, as compared with the life of a photosensitive drum. In the case where such a static eliminator is integrally disposed with a drum unit, and is replaced together with a photosensitive drum, the cost of the drum unit may unnecessarily increase. There is known, as a conventional device, a device constructed such that a static eliminator is fixedly mounted to an exhaust duct in an apparatus main body.
In the aforementioned conventional device, the static eliminator extends toward the photosensitive drum from the exhaust duct disposed away from the photosensitive drum. Accordingly, in the above configuration, the position precision of the static eliminator relative to the circumferential surface of the photosensitive drum is unstable. As a result, the light amount of static eliminating light to be irradiated onto the circumferential surface of the photosensitive drum may vary. In addition, the conventional device is provided with a moving mechanism for moving the static eliminator toward the photosensitive drum. In the above configuration, the cost of the entire apparatus may resultantly increase.
An object of the present disclosure is to provide an image forming apparatus that enables to reduce the cost of a drum unit for supporting a photosensitive drum, and to enhance the position precision of a static eliminator relative to the photosensitive drum.